VERTICAL- AND HORIZOWTAIL COMBINATIONS AT MACH NUMBERS

k experimental investigation was made at Mach numbers of 1.62, 1.93, and 2.41 of a series of tail combinations consisting of a triangular ver-tical tail attached symmetrically to a triangular horizontal tail to determine the lateral force, yawing moment, and rolling moment due to sideslip. The apex angles of both the vertical- and horizontal-tail sur-faces were varied systematically in order to obtain results for an appre-ciable range of operating conditions. The results of the investigation indicated that, for tails having subsonic leading edges and supersonic trailing edges, the lateral-force8 derivative and the yawing-mmnent derivative were predicted satisfacto-rily by the method presented in NACA TN 3071 except when the leading * edges approach a sonic condition. The theoretical rolling-moment deriva-tive was In fair agreement with the experimental derivative. For the limited tests in which both the leading and trailing edges were super-sonic, the prediction of the lateral-force derivative smd the yawing-mment derivative obtained fran NACA TN 2412 was in good agreement with the experiinentalderivatives, whereas the prediction of the rolling-mmnent derivative was fair